Log in / Log Out Custom Button

here is a very simple function that should do it:

function loginout_button_wpa89153($echo = true){
    if (is_user_logged_in()){
        $url = wp_logout_url(get_permalink());
        $anchor = "Logout";
    }else{
        $url = wp_login_url(get_permalink());
        $anchor = "Login";
    }
    $button = '<a href="'.$url.'" class="join-button">'.$anchor.'</a>';
    if ($echo)
        echo $button;
    else
        return $button;
}